As processes for producing aldehyde compounds in which a norbornene compound is used, for example, processes described in Patent Documents 1 to 3 are known.
Patent Documents 1 to 3 disclose processes in which hydroformylation of cyan norbornene is caused in the presence of a catalyst using a H2/CO gas mixture, thereby producing formyl cyan norbornene. Patent Documents 1 and 2 disclose examples in which a compound containing a metal is used as the catalyst. Meanwhile, a rhodium complex is preferably used as the catalyst since a target compound can be highly selectively obtained and a reaction pressure can be suppressed at a low level.
Patent Document 1 describes that a content of the catalyst can be set to 0.1 weight % to 10 weight % with respect to that of cyan norbornene. Patent Document 2 describes that it is possible to set a catalyst concentration to 0.5 mmol/l to 10 mmol/l and to use triaryl phosphine in a range of 3 mol to 300 mol with respect to 1 mol of rhodium.
Patent Document 4 discloses a process in which hydroformylation of an olefin compound is caused in the presence of a transition metal catalyst and a trivalent phosphoric compound using a H2/CO gas mixture. In addition, regarding a content of the metal catalyst, it is described that a content of free metal is 10 ppm to 1000 ppm in terms of a weight or volume of a catalyst composition.
Patent Document 5 describes metal ligand complex catalysts, and mentions rhodium as a metal and an organic phosphorous ligand as a ligand. Regarding use amounts thereof, it is described that a metal concentration is in a range of approximately 1 ppm to 10,000 ppm and a molar ratio of the ligand to the metal is 1:1 to 200:1 in terms of an equivalent amount of free metal.
In addition, Patent Documents 6 and 7 disclose processes in which hydroformylation of a chain-like olefin compound is caused, thereby producing an aldehyde compound.
Patent Document 6 describes hydroformylation of 7-octenal is caused in the presence of a rhodium catalyst and bisphosphite in Examples. It is described that approximately 3 ppm mol of rhodium is used with respect to 1 mol of 7-octenal, and a molar ratio of rhodium atoms to phosphorous atoms is 1/20. Meanwhile, Patent Document 6 describes in Paragraph 0084 that a content of bisphosphite is preferably 2 mol to 1000 mol with respect to 1 mol of a metal in terms of a phosphorus atom, and, in a case in which the content exceeds 1000 mol, there is a tendency of a reaction rate becoming extremely small.
In addition, Patent Document 7 describes an example in which hydroformylation of cyclohexene is caused in the presence of 3 ppm of rhodium in Examples.